Влияние экологических факторов на генетический полиморфизм в природных популяциях Fragaria vesca

Abstract

Genetic polymorphism of natural cenopopulations of wild strawberry (Fragaria vesca) from the Republic of Mari El was measured by randomly amplified polymorphic DNA (RAPD). The method of molecular genome marking based on RAPD-PCR makes it possible to determine the genetic status of populations and establish interpopulation relationships. The cenopopulations that we selected for the analysis were confined to different stages of the forest phytocenosis succession: the climatic phytocenosis and the area of the forest felling. These F. vesca cenopopulations differed in the ratio of sexual and vegetative reproduction during the maintenance of the cenopopulation size. In a felling area in conditions of greater illumination the intensity of sexual and vegetative reproduction increases. However, specimens of seed origin were not found in the felling area, since in conditions of high competition with ruderal and meadow plants, slowly developing strawberry seedlings died. The germination of seeds and plants of seed origin was noted under conditions of climatic phytocenosis. For the cenopopulation confined to the climax forest, Shannon’s diversity index and Nei’s genetic distance were 0.5179 and 0.3613 respectively. In a felling area vegetative reproduction processes predominate, so Shannon’s diversity index and Nei’s genetic distance were lower, 0.4573 and 0.3132 respectively. In a felling area revealed the loss of certain genetic clusters present in the climax forest. This indicates the loss of a strawberry genetic diversity in the transition to vegetative reproduction due to anthropogenic impact. Our data confirm the idea that climax communities with their more stable conditions can act as regenerative niches of the species.